Fire extinguishing method and apparatus



Oct. 30, 1945. L. D. MYERS FIRE EXTINGUISHING METHOD AND APPARATUS Filed Deo. 15, 1945 Patented Get. 30, 1945 UNITED STATE s PATENT OFFICE FIRE EXTINGUISHING METHOD AND APPARATU Application December 15, 1943, Serial No. 514,403

22 Claims.

This invention relates to methods of discharging a re extinguishing medium composed of carbon dioxide and water fog and apparatus for carrying out said methods.

In the application of Hilding V. Williamson, Serial No. 434,556, filed March 13, 1942, there is disclosed and broadly claimed methods and apparatus for eiecting discharge of liquid carbon dioxide in such a manner that the resultant stream of snow and vapor will possess highly effective range and penetrating characteristics as well as a large field of application or area of direct impingement. These highly desirable results are obtained by manipulating the mixture of carbon dioxide snow and vapor, during travel of the same from its zone of production to its zone of discharge to the atmosphere, so that the snow and vapor components of the mixture are segregated or formed into layers. These layers are superimposed in a discharge stream of substantially greater cross sectional dimension in one direction than in the other.

It has been determined that the re extinguishing characteristics of the discharge provided by the methods and apparatus of the above identied application can be materially improved by combining therewith a discharge of pre-formed water fog if the water fog is projected in such a, manner that the proportions of Water fog and carbon dioxide are maintained substantially uniform throughout the major cross sectional dimension of the discharge stream.

It is a primary object of this invention to provide a method of discharging a re extinguishing medium, composed of carbon dioxide and water fog, as a stream of substantially rectangular section and apparatus for carrying out said method.

A further important object of the invention is to provide a method of discharging a fire extinguishing medium as a stream of elongated cross section with the carbon dioxide snow and vapor components segregated in superimposed layers therein and with pre-formed Water fog combined with one of said segregated components, and apparatus for carrying out said method.

Another important object of the invention is the provision of a method of producing an improved discharge of a re extinguishing medium that consists of carbon dioxide snow and vapor and pre-formed water fog in which the water fog is combined with the carbon dioxide snow.

Still another important object of the invention is the provision of a method of producing an improved discharge of a re extinguishing medium that consists of carbon dioxide snow and vapor and pre-formed Water fog in which the water fog is combined with the carbon dioxide vapor.

A further object of the invention is the provision of an apparatus for producing an improved discharge of a, fire extinguishing medium that consists of carbon dioxide snow and vapor and pre-formed water fog in which the water fog is combined with the carbon dioxide snow.

Another object of the invention is the provision of apparatus for producing an improved discharge of a fire extinguishing medium that consists of carbon dioxide snow and vapor and pre-formed water fog in which the Water fog is combined with the carbon dioxide vapor.

Other objects and advantages of the invention will be apparent during the course of the following description.

In the accompanying drawing forming a part of this specification and in which like numerals are employed to designate like parts throughout the same:

Figure 1 is a front elevational view of one form of fire extinguishing medium discharge apparatus embodying this invention,

Figure.2 is a transverse sectional view taken on line 2 2 of Fig. 1. and

Figure 3 is a transverse sectional View of a modied form of fire extinguishing medium discharge apparatus.

In the drawing, wherein for the purpose of illustration are shown the preferred embodiments of this invention, and first particularly referring to Figs. 1 and 2 inclusive, the reference character 5 designates a. liquid carbon dioxide supply pipe for the discharge apparatus. It will be appreciated that this pipe 5 may represent a portion of a pipe line which leads from the discharge apparatus to the source of supply of the liquid carbon dioxide. 'Ihis source of supply either may be a storage container of the type disclosed in Patent No. 2,143,311, issued to Eric Geertz, in which the liquid carbon' dioxide is maintained at a substantially constant subatmospheric temperature, and its corresponding low vapor pressure, or a bank of cylinders in which the liquid carbon dioxide is conned at the changing high vapor pressures which correspond with the prevailing temperatures of the surrounding atmosphere. Although the size of the discharge apparatus embodying this invention may be such as to permit the apparatus to be employed on the end of a hose line for direct manual manipulation, the full benets of the invention may best be obtained when the discharge apparatus is of such a size as to require it to be employed as a part of a fixed ilre extinguishing system, or to require it to be mounted on some form of wheeled vehicle or carriage which is movable to permit the field o! application of the extinguishing medium to traverse the involved area and to wipe out the fire as the carriage or vehicle progresses. A ground fire involving owing flammable liquids presents an excellent example of a need for mounting this type oi' discharge apparatus on a wheeled vehicle or carriage.

The pipe section 5 is threaded at 3 for proper connection with a; suitable supply line. The remaining end of this pipe section is connected by welding, or the like, to the right angularly arranged manifold 1 that extends in opposite directions. Suitable couplings 8 are connected to the opposite ends of the manifold pipe l and have short nipples 9 threadedly connected in their remaining branches. These nipples are connected to the T-couplings I0 which are employed for connecting the apertured discharge pipes II to the said nipples. Fig. 1 discloses the use oi four of these apertured discharge pipes which are arranged in parallel pairs. Each one of these discharge pipes II is suitably closed at its outer end and is provided with a longitudinally arranged series of apertures I2. The apertures of each series are spaced at suitable intervals and, it will be noted by inspecting Fig. 2, that they face in a. general rearward direction rather than a forward direction.

It will be appreciated. that when liquid carbon dioxide is released to [the atmosphere through the discharge apertures I2, the carbon dioxide will vaporize and ash to a uniform mixture of vapor and snow as a result of the sudden drop in pressure. The percentage of the liquid carbon dioxide that flashes to snow will depend on the temperature of the liquid carbon dioxide at the place of storage. It will be explained more fully at a later point in the description that the mixv#ture of carbon dioxide snow and vapor produced at each one of the discharge apertures I2 is .to be manipulated in such a manner that the snow and vapor components may be discharged to the atmosphere in a segregated condition with the dis-- charges from the apertures of the two pipes II connected to a T-coupling Ill being merged lengthwise of the discharge apparatus so as to provide a continuous, elongated discharge stream. For that purpose, each pair of discharge pipes II connected to a T-coupling I0 are suitably arranged within a merging and segregating chamber I3'. I-t will be seen by inspecting Fig. 1 that these two chambers I3 extend the full length of the discharge apparatus and, when the apparatus is held or positioned in the manner illustrated in Figs. 1 and 2, these chambers form the top and bottom of the discharge device. The opposite ends of the merging and segregating chambers I3 are closed by the two end plates Il. 'I'hat is t0 Say, one end plate Il is provided at each end of the discharge apparatus and closes the adjacent ends of both of the chambers I3. These end plates, therefore, help to maintain the chambers properly spaced and provide rigidity for the discharge apparatus.

Each one of these merging and segregating chambers I3 is provided with a rear wall I5 that is of semi-circular shape in section. These rear walls merge into parallel walls I8 which cooperate at their forward edges with the forward edges of the end plates Il to provide the open fronts, or discharge openings, for the two chambers I3.

These open fronts. therefore. lie directly opposite the curved rear walls Il. Fig. 2 discloses the dischargepipes II asbeingweldedat IItothe upper and lower wall portions I3 of the two chambers I3. The discharge pipes II, therefore, cooperate with the top and bottom wall portions I3 of the two chambers to lend rigidity to these chambers and to the entire discharge apparatus. The adjacent or inner side walls Ilof the two chambers are interconnected and braced at a suitable number of points by the straps I3. To fur-ther strengthen the chambers I3, a pair of angle irons are provided for each half portion of the discharge apparatus arranged on opposite sides o! a water supply Pipe which will be specincally referred t0 later on. The angle irons of each pair are connected by welding at the points 2l and 2|. 'I'he longitudinal edges of the oppositely extending branches of these two angle irons are welded at 22 to the inner side portions of the two merging and segregating chambers I3.

By inspecting Fig. 2, it will be seen that the longitudinal series of discharge apertures I2 for each pipe Il face or point toward the zone where its associated rear chamber wall I3 merges with the outer chamber wall I3. It will be appreciated, therefore. that the separate jets of carbon dioxide snow and vapor mixture produced by the several orifices or apertures I2 will iirst impinge against the interiors of the two chambers I3 at these chamber wall merger zones.

The mode of operation of this form of carbon dioxide discharge apparatus now will be described. Liquid carbon dioxide of any desired temperature will flow under its own vapor-pressure through the pipe members 5, l, 3, l, Il and II so as to be dischargedthrough the two 1ongitudinal series of apertures I2 formed in the two pairs of parallel pipes II. 'Ihe liquid carbon dioxide in these discharge pipes I I will be released to the interiors of the chambers I3 through the apertures I2 and, due to the sudden drop in pressure which occurs as a result of this release, the liquid carbon dioxide will be converted to a mixture of snow particles and vapor. Each aperture I2 will provide a separate jet or stream of the carbon dioxide mixture. 'I'hese jets or streams will partake of straight line motion until their paths are obstructed by the inner surfaces of the chambers I3. 'I'he curved rear surfaces of these two chambers will cause the flowing mixtures of carbon dioxide snow and vapor to be deflected so that the normal straight line motion will be converted .to a curvilinear motion. In addition to partaking of this Acurvilinear motion, the snow and vapor of the several streams or jets released into each one of the two elongated chambers I3 will be permitted to spread longitudinally of the chambers with the result that the mixtures of the several streams or jets will merge to form a continuous mass equal in length to each continuous chamber I3. It is a well recognized law or principle of physics that any object or material which is set in motion will travel in a straight line unless some force is applied thereto which will deflect it from such a path of movement. Additionally. the force required to deilect the object or material from its straight line motion depends onthe velocity and the mass or density of the object or material being deflected.

With this principle in mind, it will be appreciated that the curved inner surfaces of the rear walls l5 of the two chambers will function to accomplish a change in the direction of motion of dash lines A 0f Fig. 2.

the released carbon dioxide snow and vapor mix ture and this change will be from a straight line motion to a curvilinear motion. These curved chamber wall surfaces, therefore, provide the opposing force referred toabove. As the carbon dioxide snow of the mixture is many times more dense than the carbon dioxide vapor, and as the velocity of both of these components is the same, the snow oil'ers more resistance to the deilecting force provided by the rear walls of the chamber. The snow, therefore, will force its way to the outer sides of the curvilinear paths of flow of the material with the result that the snow will displace the vapor and force it to seek a path of flow away from the inner surfaces of the two chamber walls. The diiferencelin density of the snow as compared to the vapor,'therefore, brings about a segregation of these two components. That is to say, the snow will form a flowing'layer in contact with the inner wall surface of each one of the chambers while the vapor will form a superimposed layer spaced from the surface of the chamber wall.

To further explain this segregating action, it will be appreciated that the segregating of the snow and vapor components will not be complete for a small amount of the vapor will be trapped by the snow particles and be compelled to ilow therewith while a small amount of the lighter, smaller snow particles will be carried along with the vapor. Furthermore, there will be a merging or blend zone between the concentrated layer of snow and the displaced layer of vapor. That is to say, the snow and vapor will not be sharply defined into two clearly distinguishable layers. Consequently, the expression segregating the snow and vapor components into separate layers will not be one hundred percent accurate but it is believed that the expression can be employed for defining the type of discharge provided by the apparatus and for distinguishing from a conventional discharge in which the snow and vapor are uniformly mixed.

The desired segregation of the snow and vapor is accomplished by the time the flowing material reaches the open front of each chamber I3. By inspecting Fig. 2, it will be appreciated that the snow layer for each chamber will be adjacent the inner wall I6 while the vapor layer will be arranged outwardly ofthe snow layer or adjacent the discharge pipe II. It will be appreciated, therefore, that each chamber I3 will discharge a stream of carbon dioxide whichwill be continuous throughout its length. These two discharges will be arranged in parallelism to each other and will start out by being separated from each other a distance equal t the spacing of the The two layers of snow from the two chambers I3 will lie adjacent each other while the two layers of vapor will be located outwardly of the snow layers and will function to shield the snow layers from the surrounding atmosphere with the exception of the regions at the opposite ends o f the complete discharge apparatus. Of course, with no physical barrier lying between the two spaced discharges produced by the two chambers I3, that is beyond the open faces of these chambers, the snow of the two inner or adjacent layers will blend or ow together by moving inwardly of the lines A. This blending together or flowing toward each other will not take place immediately and will not occur until the momentum or inertia of the discharge has been substantially dissipated. Consequently, there will be provided a space or area between the two unes A and extending the full length of the discharge apparatus which will not be occupied by the carbon dioxide discharge from the two chambers I3. This unoccupied4 space is utilized in a manner now to be described.

A pocket or recess is provided by the adjacent walls Il of the two chambers, vthe end plates I4 and the two pairs of angle irons I9. This pocket or recess is employed for receiving a water fog generating head 2l. This head is shown in Fig. 1 as extending the full length of the discharge apparatus. It is oi' hollow construction and is provided with a front wall 2l that includes the angularly arranged wall portions 25 and 26. These angular-ly arranged wall portions are provided with two longitudinal series of spaced apertures 21 and 2l respectively. Figs. 1 and 2 disclose these apertures 21 and 28 as being arranged in transversely aligned pairs. That is to say, the apertures 21 are opposed to the apertures 28 so that the streams of water that are discharged from these opposed apertures will impinge against each other with the result that the water of both streams will be highly atomized and water fog will be generated. The angle of projection of the water fog produced by each pair of apertures 21-'28 is represented by the dash lines B in Fig. 2.

Water is supplied to the interior of the water fogl generating head 23 `by the supply pipe 24. This water should be under a suitable pressure head. It has been determined that a pressure ranging from to 200 pounds per Square inch will effect proper fogging of the water.

It will be appreciated that impingement of the two streams of water from each opposed pair of apertures 21 and 28 will effect a projection angle which is represented by the lines B in Fig. 2

insofar as a section through two apertures 21 and 23 isy concerned. It will-be appreciated, also, that the water fog pattern produced by each pair of apertures 21 and 28 will be nearly cone shape when viewed at right angles from the section of Fig. 2. Consequently, the fog patterns of adjacent pairs of apertures 21 and 28 will merge lengthwise of the fog generating head 23, or lengthwise of the space or gap that is provided between the dash lines A of Fig. 2 which represent the inner margins of the two carbon dioxide discharge streams. Therefore, this space or gap will be filled with water fog. The angle of projection of the water fog represented by the lines B of Fig. 2 shows that some of the water fog will be caused to directly impinge the adjacent sides of the two snow layers of the spaced carbon dioxide discharges. Consequently, water fog will 'be entraincd by the snow layers.

In Fig. l the extreme end pairs of water discharging apertures of the fog generating head 21 are identied by the reference characters`21a and 28a'to distinguish them from the remaining apertures 21 and 28. The water fog generated by these two pairs of end apertures 21a and 28a will function to close oft the opposite ends of the gap or space that is left between the two carbon dioxide discharges produced by the chambers I3. That is to say, the water fog generated by the opposite end pairs of apertures 21a and 28a seal off the opposite ends of this gap or space from the surrounding atmosphere and thereby excludes air from the gap or lspace in which the remainder of the water fog is generated. This enables the water fog generated by all of the .pairs of apertures 21 and l28 to have the voids with a carbon dioxide atmosphere instead of an air atmosphere. It will be appreciated, therefore, that the water fog delivered to the zone of the ilre will not carry trapped or entrained air to the iire. The delivery of air to a re by an extinguishing medium is very objectionable because the air provides the iire with combustion supporting oxygen.

From the above description, it will be appreciated that the discharge provided by the apparatus of Figs. 1 and 2 will consist of a composite stream of elongated or rectangular shape in transverse section. 'I'his stream will be made up of a. top layer and a bottom layer of carbon dioxide vapor. Inwardly of these two vapor layers will be two layers of carbon dioxide snow with water fog entrained therein. Between these two carbon dioxide snow and water fog layers there will be a core of water fog with the voids between the water droplets filled with carbon dioxide. Due to the extremely low temperature of the carbon dioxide snow, the water droplets entrained thereby will be frozen to water-ice particles.

To prevent too rapid a transfer of heat from the water flowing through the head 23 to the carbon dioxide snow flowing in contact with the inner walls I6 of the two chambers I3, a suitable layer of insulating material 29 may be interposed between the rear and side walls of the fog generating head 23 and the opposed walls I6 and angle irons I9.

It will be obvious to any one skilled in the art that the discharge pipe II may be moved to the inner sides of the chambers I3, or into positions adjacent the inner walls I8 of these chambers that are positioned next to the water fog generating head 23. With the discharge pipes positioned in this manner and rotated approximately 30 to cause the apertures I2 to deliver their jets of carbon dioxide snow and vapor mixtures against the proper zones of the inner surfaces of the chambers I3, the positioning of the carbon dioxide snow and vapor layers relative to the water fog will be changed. This modified discharge stream will consist of top and bottom layers of carbon dioxide snow with layers of carbon dioxide vapor and entrained water fog lying inwardly of the snow layers, and with a core of water fog.

It, also, will be appreciated that by placing control valves in the carbon dioxide and water supply lines that are connected to the pipes 6 and 24 respectively, the flow of the carbon dioxide or the water to the discharge apparatus may be stopped at any time to provide a, discharge of water fog by itself or a discharge of the carbon dioxide by itself. The water fog discharge pattern and the carbon dioxide discharge pattern are such that these materials can be used separately at different stages of the extinguishment of different types of res.

Fig. 3 has been presented to illustrate certain modifications that can be made in the methods and apparatus embodying this invention. This figure specically illustrates the use of one pair of apertured carbon dioxide discharge pipes II carried by the T-coupling I and associated with a single merging and segregating chamber I3. The discharge pipes I I are provided with the same longitudinal series of apertures I2 that are directed to cause the jets of carbon dioxide snow and vapor mixture to impinge against the point of merger between the straight wall portion I6 and the rear curved wall portion I of the chamber. The opposite side of this chamber is provided with the second straight wall 60. 'I'he discharge pipes II are welded at I1 to the adjacent wall I6 of the chamber. When only one pair of discharge pipes II is employed, the T-coupling I0 can be connected to the pipe 3a that extends directly to the carbon dioxide supply line.

The water fog for this carbon dioxide discharge is produced by the head 30 that extends longitudinally of andk is closely positioned with respect to the chamber side wall I6 to which the discharge pipes II are attached. The front wall of this water fog generating head 30 is provided with the angularly arranged wall portions 3I and 32 and these wall portions are provided with the longitudinal series of apertures 33 and 3l, re-

spectively. The Jet of water delivered by the opposed apertures 33 and 34 will impinge to generate the water fog that is projected through the angle represented by the dash lines C. Water under the desired pressure head is supplied to the fog generating head 30 by the pipe line 35 that is threadedly connected to the nipple 38 properly secured to the rear wall of the fog generating head 30. A suitable layer of insulating material 31 may be interposed between the fog generating head 30 and the adjacent side wall I6 of the carbon dioxide snow and vapor segregating chamber I3.

With this form of discharge apparatus, a discharge stream will be provided that will consist of a bottom segregated layer of carbon dioxide snow with a layer of carbon dioxide vapor lying above the snow layer. Above this carbon dioxide discharge there will be projected a pattern of water fog. Due to the angle of projection of this water fog, a portion of the same will impinge against the carbon dioxide vapor layer and will be entrained by this layer. The projection angle of the water fog is such, however, that a portion of the water fog will not be entrained by the carbondioxide vapor layer of the carbon dioxide discharge.

It will be perfectly obvious to persons skilled in the art that two assemblies of the character shown in Fig. 3 may be associated with each other so that the two carbon dioxide snow and vapor segregating chambers I3 will lie in contact with each other and the two water fog generating heads 30 will lie on the outer sides of the two chambers I3. This combined type of discharge apparatus will produce a flre extinguishing discharge that will consist of a dense carbon dioxide snow core that is produced by the snow layers discharged by the two chambers I3 with carbon dioxide vapor layers arranged above and below the dense snow core layer and with top and bottom layers or patterns of water fog in which portions of the water fog will be entrained by or carried along with the carbon dioxide vapor layers.

It is to be understood that the forms of the invention herewith shown and described are to be taken as preferred examples of the same and that various changes in practicing the hereindescribed method and in the shape. size, and arrangement of parts of the apparatus that is shown as being capable of carrying out the method, may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described the invention, I claim:

1. A method of discharging a fire extinguishing medium, comprising effecting sudden release of liquid carbon dioxide to lower its pressure sumciently to form snow and vapor, discharging the carbon dioxide snow and vapor to the atmosphere in the form of a stream oi rectangular shape in cross section, separately generating water fog in a zone paralleling and co-extensive with the major cross sectional dimension of the rectangular carbon dioxide stream, and projecting the generated water fog so that a portion of the same will be entrained by the carbon dioxide stream.

2. A method of discharging a iire extinguishing medium, comprising effecting sudden release of liquid carbon dioxide along the length of two zones to lower its pressure sufilciently to form snow and vapor, discharging the carbon dioxide snow and vapor to the atmosphere from both of said zones to form parallel streams of rectangular shape in cross section, separately generating water fog in a zone paralleling and coextensive with the major cross sectional dimension of each of the two rectangular carbon dioxide streams, and projecting the generated water fog so that portions of the same will be entrained by the carbon dioxide streams.

3. A method of discharging a iire extinguishing medium, comprising effecting sudden release of liquid carbon dioxide along the length of two elongated zones to lower its pressure suiliciently to form snow and vapor, discharging the carbon dioxide snow and vapor to the atmosphere from both of said zones to form parallel streams of rectangular shape in cross section, separately generating water fog in a zone lying between and co-extensive with the major cross sectional dimension of each of the two rectangular carbon dioxide streams, and projecting the generated water fog so that. portions of the same will be entrained by the carbon dioxide streams.

4. A method of discharging a iire extinguishing medium, comprising eecting sudden release of carbon dioxide to lower its pressure sufiiciently to form snow and vapor, owing said snow and vapor along a curvilinear path arranged to terminate in a discharge zone of greater width than depth in cross section to effect segregation of these components, forming the segregated snow and vapor components into a stream discharging from the entire width of the discharge zone, separately generating water fog in a zone paralleling and co-extensive with the width of the said discharge zone, and projecting the generated Water fog so that a; portion of the same will be entrained by the carbon dioxide stream.

5. A method of discharging a fire extingushing medium, comprising effecting sudden release of liquid carbon dioxide to lower its pressure sufiiciently to form snow and vapor, iiowing said snow and vapor along a curvilinear path arranged to terminate in an elongated discharge zone to effect segregation of these components, forming the segregated snow and vapor components into a discharge having a width substantially corresponding with the length of the elongated discharge zone and with the segregated snow component dening one surface of the discharge While the segregated vapor defines the other surface, separately generating water fog in a zone paralleling and co-extensive with the length of the said elongated discharge zone, and projecting the generated water fog so that a portion of the same will be entrained by the segregated vapor portion of the carbon dioxide discharge.

6. A method of discharging a re extinguishing medium, comprising effecting sudden release of liquid carbon dioxide to lower its pressure sufilciently to form. snow and vapor, owing -said snow and vapor along a curvilinear path arranged to terminate in an elongated discharge zone to eiect segregation of these components, forming the segregated snow and vapor components into a stream having a width substantially corresponding with the length of the elongated discharge zone and with the segregated snow deilning one surface of the stream while the segregated vapor defines the other surface, separately generating water fog in a zone paralleling and co-extensive with the length of the said elongated discharge zone, and projecting the generated water fog so that a portion of the same will be entrained by the segregated snow portion of the carbon dioxide stream.

7. A method of discharging a. fire extinguishing medium, comprising effecting sudden release of liquid carbon dioxide to lower its pressure sufficiently to form snow and vapor, flowing said snow and vapor along a curvilinear path arranged to terminate in an elongated discharge zone to eiect segregation of these components, forming the segregated snow and vapor components into a stream having a width substantially corresponding to the length of the elongated discharge zone and with the snow and vapor segregations arranged in the stream so that the vapor segregations will lle outwardly of the snow segregation, separately generating water fog, and projecting the water fog so that portions of the same will be entrained by the snow aggregations.

8. A method of discharging `a lire extinguishing medium, comprising effecting sudden release of liquid carbon dioxide to lower its pressure sufciently to form snow and vapor, iiowing said snow and vapor along parallel curvilinear paths arranged to terminate in parallel elongated discharge zones to eiect segregation of these components as a result of their difference in density, forming the segregated snow and vapor components of said parallel paths into streams discharging from the entire lengths of the elongated discharge zones, separately generating water fog in a zone paralleling and co-extensive rwith the length of the said elongated discharge zones, and projecting the generated water fog so that portions of the same will be entrained by the two carbon dioxide streams.

9. A method of discharging a re extinguishing medium, comprising eiecting sudden release of liquid carbon dioxide along the lengths of two spaced zones to lower its pressure sulciently to form snow and vapor, discharging the carbon dioxide snow and vapor to the atmosphere from both of said zones to form parallel, spaced streams of elongated cross section, separately generating water fog, and projecting the water fog into the the space that lies between the carbon dioxide streams.

10. A method of discharging a iire extinguishing medium, comprising effecting sudden release of liquid carbon dioxide along the lengths of two spaced zones to lower its pressure sufficiently to form snow and vapor, owing said snow and va.- por along parallel curvilinear paths arranged to terminate in spaced elongated discharge zones to eiect segregation of these components as a result of their difference in density, forming the snow and vapor components oi.' said parallel paths into two spaced streams each of which has a greater width than thickness, separately generating water fog, and projecting the water fog into the space that lies between the two carbon dioxide streams.

11. A method of discharging a nre extinguishdioxide through ing medium, comprising eiiecting sudden release of liquid carbon dioxide along the lengths oi' two spaced' zones to lower its pressure suiiiciently to form snow and vapor, owing said snow and vapor along parallel curvilinear paths arranged to terminate in spaced elongated discharge zones to ei'feet segregation of these components as a result oi their diilerence in density. forming the snow and vapor components of said parallel paths into two spaced streams each of which has a greater width than thickness and with the snow and vapor components oi each stream arranged in separate layers, separately generating water fog, and projecting the water fog into the space that lies between the twovcarbon dioxide streams.

12. A method oi' discharging a fire extinguishing medium, comprising effecting sudden release o! liquid carbon dioxide along the lengths of two spaced zones to lower its pressure sulciently to form snow and vapor, iiowing said snow and vapor along parallel curvilinear paths arranged to ter-- minate in spaced elongated discharge zones to eifect segregation of these components as a result oi their dierence in density, forming the snow and vapor lcomponents of said parallel paths into two spaced streams each of which has a greater width than thickness and with the snow and vapor components oi.' each stream arranged in separate layers with the snow layers arranged adjacent each other, separately generating water fog, and projecting the water fog into the space that lies between the snow layers of the two carbon dioxide streams.

13. A method of discharging a ilre extinguishing medium, comprising conducting liquid carbon dioxide to a relatively long region of release, discharging theliquid carbon dioxide through a plurality ofconstricted oriilces arranged along said region to 'permit sudden expansion of the liquid to eect its conversion into snow and vapor, maintaining the ilowing snow and vapor in conilnement until they merge along the length oi said reglon; causing the snow and vapor to partake of curvilinear motion while thus conilned so that the diil'erence in density of the snow and vapor will eilect the segregation of these components, ilnally discharging to the atmosphere along the length of said region the thus segregated snow and vapor, separately generatng water fog in a zone paralleling and co-extensive with the length of the long region oi' release i'or the liquid carbon dioxide, and projecting the generated water fog so that a portion of the same will be entrained by the carbon dioxide stream.

14. A method of discharging a lire extinguishing medium, comprising conducting liquid carbon spaced parallel flow paths extending longitudinally of a relatively long region of release, discharging the liquid carbon dioxide through a plurality oi' constricted oriilces arranged along each ilow path to permit sudden expansion of the liquid to eil'ect its conversion into snow and vapor, maintaining the ilowing snow and vapor for each flow path in a separate zone of connement until they merge lengthwise of their zone, causing the snow and vapor in each zone to partake of curvilinear motion while thus confined so that the diil'erence in density of the snow and vapor will effect segregation of these components, inally discharging to theA atmosphere from said zones their segregated snow and vapor as two parallel, spaced streams of elongated cross section, separately generating water i'og, and projecting the water i'og into the space that lies between the two carbon dioxide streams.

l5. A method of discharging a nre extinguishing medium, comprising conductingl liquid carbon dioxide through spaced parallel iiow paths extending longitudinally of a relatively long region of release, discharging the liquid carbon dioxide through a plurality of constricted orifices arranged along each now path to permit sudden expansion of the liquid to eil'ect its conversion into snow and, vapor, maintaining the iiowing snow and vapor for each now path in a separate zone of conilnement until they merge lengthwise of their zone, causing the snow and vapor in each zone to partake of curvilinear motion while thus confined so that the diierence in density of the snow and vapor will eiiect segregation of these components, ilnally'discharging to the atmosphere from said zones their segregated snow and vapor as two parallel, spaced streams of elongated cross section, separately generating water fog. and projecting the water fog into the space that lies between the two carbon dioxide streams with the angle of projection oi' the water fog being arranged relative to the two carbon dioxide streams so that portions of the water fog will be delivered to and entrained by the two carbon dioxide streams.

16. Fire extinguishing apparatus comprising a chamber of greater width than depth in cross section having a discharge opening co-extensive with the cross section of the 'chamber and a transversely curved wall lying opposite said opening, means for releasing throughout the width of said chamber carbon dioxide snow and vapor in such a manner as to cause the snow and vapor to ow over said curved wall in reaching the discharge opening whereby the snow and vapor will be segregated into diiierent portions of the stream discharged through the chamber opening, and a water fog generating head extending lengthwise oi.' the aforesaid chamber and positioned to project the water fog so that a portion oi' the same will impinge against and be entrained by the carbon dioxide stream.

17. Fire extinguishing apparatus. comprising parallel elongated chambers arranged adjacent each other, each one of said chambers having a discharge opening extending the lengththereoi and a transversely curved wall lying opposite said opening, means in each chamber for releasing into the length thereof carbon dioxide snow -and vapor in such a manner as to cause the snow and vapor to flow over said curved wall i'n reaching the discharge opening whereby the snow and vapor of each chamber will be segregated into diierent portions of the stream discharging through the chamber opening, and an elongated water fog generating head arranged lengthwise oi' the aforesaid elongated chambers for projecting water fog into the paths of the two carbon dioxide streams.

18. Fire extinguishing apparatus comprising a chamber of greater width than depth in cross section having a discharge opening co-extensive with the cross section of the chamber and a transversely curved wall lying opposite said opening, means for releasing throughout the width oi said chamber a plurality of longitudinally spaced jets of carbon dioxide snow and vapor with the jets so directed that the snow and vapor will be caused to ilow over said curved wall in reaching the discharge opening whereby the snow and vapor will be segregated into diil'erent portions of the stream discharged through the chamber opening, and a hollow head extending lengthwise of and adjacent to the aforesaid chamber, said head having formed therein two longitudinal series of angularly arranged apertures for discharging streams of Water which will lmpinge to produce water fog that is projected partly into the path of the carbon dioxide stream discharged through the chamber opening.

19Fire extinguishing apparatus, comprising two parallel elongated chambers arranged in spaced relation to each other, each one oi said chambers having a discharge opening extending the length thereof and a transversely curved wail lying opposite said opening, means in each chamber for releasing a. plurality of longitudinally spaced jets of carbon dioxide snow and vapor with the jets so directed that the snow and vapor will be caused to iiow over said curved wall in reaching the discharge opening whereby the snow and vapor will be segregated into different portions of the discharges through the chamber openings, and a water fog generating head positioned in the space between the two elongated chambers and arranged to project the generated Water fog partly into the paths of the carbon dioxide discharges from the two chamber openings,

20. Fire extinguishing apparatus, comprising means for projecting carbon dioxide snow and vapor as a stream of greater width than depth in cross section, and means for separately generating water fog and projecting the water fog in of liquid carbon dioxide to lower its pressure sufiiciently to form snow and vapor, discharging the carbon dioxide snow and vapor to the atmosphere in the form of a stream oi greater width than depth in cross section, releasing to the atmosphere along a zone paralleiing and co-extensive with the width of the carbon dioxide stream a second and different nre extinguishing iiuid, and so projecting the second fire extinguishing fiuid that it will be delivered to the point of application conjointlywith the carbon dioxide.

22. A method of discharging a re extinguishing medium, comprising eecting sudden release of liquid carbon dioxide along the length of two zones to lower its pressure suiciently to form snow and vapor, discharging the carbon dioxide snow and vapor to the atmosphere from both of said zones to form parallel streams each of which is of greater width than depth in cross section, releasing to the atmosphere along a zone lying between the parallel carbon dioxide streams a second and different re extinguishing fluid, and so projecting the second fire extinguishing fluid that it will be delivered to the point of application conjointly with the carbon dioxide.

LEONARD D. MYERS. 

